This was a series with a huge Trek like following and with the ORGINAL stars and it still tanked.
True. In it's prime, the TV show drew about 1.5 times as many viewers as TNG did. Considering that, compared to the Trek movies, the first X-Files movie (1998) didn't really do all that well. INS also came out in 1998, and that "bad" Trek movie made only ("only") $13 million less in the U.S. than the X-Files movie did (most of that difference based on first two weeks take). FC (1996) made more money in the U.S. than the X-Files movie did.
The X-Files was must-see TV in its time. It just didn't go to the big screen as well as Star Trek did.